Presumably they are sock-puppets, but on top of that are they doing something else – such as tournament stuffing, ratings manipulation (throwing games against each other in order to boost one), playing man-in-the-middle, using a program to cheat, ...?

multiple accounts , one player. Playing in the same tournament boosting 1 account.

probably there is no “cheat” in his Playing.But is not honest. I don’t have any problem of playing a matchand get a kick in the ass by Szandor, Julien, Goldric etc...But playing against a false account is out of the Sports ethic.